rn041.hs:7:1: warning: [-Wunused-top-binds (in -Wextra, -Wunused-binds)]
    Defined but not used: ‘f’

rn041.hs:9:1: warning: [-Wunused-top-binds (in -Wextra, -Wunused-binds)]
    Defined but not used: ‘g’

rn041.hs:10:1: warning: [-Wunused-top-binds (in -Wextra, -Wunused-binds)]
    Defined but not used: ‘h’